When in the Arduino IDE I see that there are multiple tabs at the top for different sketches. It seems to me that when I hit upload it should only upload the current tab I’m working in but some of the error messages I’ve gotten say things about not being able to find or upload code from a different …

[image] rapskallyun: does IDE try to upload all the sketch tabs Yes it does. [image] rapskallyun: and I need to open a new instance/window every time I want to work with a single sketch? Yes :smiling_face_with_sunglasses:

[image] rapskallyun: When in the Arduino IDE I see that there are multiple tabs at the top for different sketches. I think the more accurate way to put this is that there are multiple tabs for different source code files that constitute components of a single sketch.

One sketch folder can contain several files. The most common arrangement is a single ino, a single .h and multiple cpp. It can also be multiple ino but that comes with special rules and offers no advantage that I know of. These arrangements are for normal user sketches NOT library development.

[image] sonofcy: offers no advantage that I know of It offers the following advantages: Automated function prototype generation Doesn't require an understanding of the concept of " translation units " I accept that some advanced users will not consider either of those to be advantages. Howev…

I’m not even intermediate yet, I just started this week and overall I’m having a blast and enjoying learning all this stuff. a few things are frustrating and confusing but I’ll keep trying and asking for help so I can get better.

[image] rapskallyun: multiple tabs at the top for different sketches. Let's try to clarify what a sketch is. A sketch is a directory on your PC. It can contain multiple files but it must have one ino file with the same name as the directory.

But aren’t they processed in alphabetical order? And at that level, will they know about forward declarations, etc?

All .ino files are concatenated into a single file. The generated function prototypes are added at the top of that file. So you can call any function from any of the .ino files at any point in the sketch, without needed to manually add a function prototype/forward declaration before that point, exa…

I had the same question about opening a new sketch - why is a new instance window of the IDE opened instead of adding a new tab to the current instance but I guess opening a new instance of the IDE is necessary or expected behavior. Regarding the tabs in any given instance, I have ESP32_SPI_9341.h …

A second copy of the IDE opens if you open a second sketch (folder). If you have an .ino and a .h file in the sketch folder, they will get opened in separate tabs. There is no need to close the second tab; it is there as a convenience in case you need to edit it. Most #included .h files are NOT in…

Maybe a stupid question

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Maybe a stupid question

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